Dr Usha Zehr Barwale, chief technical officer and joint director
of research, Mahyco
An expert Geneticist, Dr Zehr has been the brain behind the development
of Bt brinjal at Mahyco.
Dr Zehr is the joint director of Research at Mahyco, India. She is
responsible for research on plant biotechnology, technology transfer to
farmers, utilization of new technologies and tools, including
biotechnology for improving the quality and productivity of seeds and
agriculture.
Insect-tolerant or Bt brinjal expressing the Bacillus thuringiensis
cry1Ac gene has been developed to reduce FSB pest-related damage in the
brinjal crop, and increase farmers' profitability by way of increased
marketable yield and protect the environment pesticides overuse.
Ex-ante studies have indicated that deploying Bt brinjal would bring
down the costs of cultivation of brinjal, as the contribution of
chemical pesticides to brinjal cultivation costs is significant, and
highest amongst vegetables in India.
Dr Zehr says, “After receiving the biological material, plant
transformation began at the Mahyco Research Facility. After the
transformed plants were generated, high performing events were selected
and these went into breeding program for transferring the trait to
number of genotypes. At this stage, we also started our partnership
with ABSPII, which included three public sector partners in India, two
in Bangladesh and one in the Philippines. The technology was
transferred to their chosen varieties.�
“All the regulatory guidelines were followed and all biosafety studies
were conducted as stipulated. These studies all require the protocol
for conduct of studies be approved by RCGM/GEAC before undertaking the
study. All toxicity studies were conducted at third party, government
approved facilities. Our team was engaged in the entire process of
development of the product,� adds Dr Zehr.
More on Dr Usha Zehr Barwale
- Dr Zehr received her MS (1985) and PhD (1987) in agronomy from
the University of Illinois, Urbana-Champaign while working as a
research assistant. She earned her BSc (Microbiology) in 1981 from
Wilson College, University of Bombay and a diploma in clinical analysis
from Sophia College, Bombay in 1982.
- Dr Zehr worked as a geneticist in the Sorghum and Millet
Improvement Program at Purdue University, US from 1991-96.
- She serves on a number of boards such as the MS Swaminathan
Research Foundation, Barwale Foundation, Sankara Netralaya and Donald
Danforth Plant Science Center. She served as a member of the Technical
Advisory Committee of the CGIAR in 1997-2002. She is a member of other
committees such as the Private Sector Committee of the CGIAR,
Intellectual Property Committee of the International Seed Federation,
National Biotechnology Network, World Water Commission and Department
of Biotechnology, Government of India. She is also director of the
Mahyco Vegetables Seeds, Jalna.
- She has been involved in the founding or functioning of several
charitable organizations such as Shri Ganapati Netralaya at Jalna,
Maharashtra.
Dr Ponnuswami
Balasubramanian, principal
investigator and former director, Center for Plant Molecular Biology,
Tamil Nadu Agricultural University (TNAU), Coimbatore
An eminent agri-scientist and expert, he was instrumental in evolving
Bt brinjal with funds from DBT and USAID.
The role of Dr P Balasubramanian involved the interfacing between his
group at TNAU on one side and DBT and ABSPII (USAID) on the other. As
per the MOU signed between Mahyco and TNAU, seeds of the target
varieties were sent to Mahyco for crossing TNAU varieties with the
Mahyco line harboring the EE1 event. Then the F1 seeds of the
respective varieties were received by TNAU and backcrossing started at
TNAU greenhouses using TNAU target varieties as recurrent parents.
“The idea was to select the best from among the backcross populations
expressing the insecticidal protein at the required level while the
original genetic backgrounds of the target TNAU varieties were retained
as well. Theoretically, a population of BC3F2 (third back cross
population selfed twice) would do for this purpose.� says Dr
Balasubramanian
While explaining his role, he says “I had to submit the reports on
ongoing work to appropriate reviewing authorities at the university
(Institutional Biosafety Committee) level and national (Review
Committee on Genetic manipulation, Genetic Engineering Approval
Committee, DBT Task Force Meetings) levels and international (ABSPII)
levels. Awareness campaigns for public awareness had to be conducted
with generous support from Biotech Consortium of India Limited and
ABLE.�
More on Dr Ponnuswami Balasubramanian
- Dr Balasubramanian is the former director of Center for Plant
Molecular Biology (CPMB) and was involved in establishment of Rice
Transformation Facility at TNAU in 1996 with financial support from the
Rockefeller Foundation New York.
- DBT with its funding assigned him the work on cloning antifungal
genes from Trichoderma spp. for use against Rhizoctonia solani, the
invincible soil-borne plant pathogen.
- He has worked in evolving several transgenic lines of elite rice
cultivars of Tamil Nadu expressing resistance to sheath blight and
bacterial blight by pyramiding genes encoding a chitinase, a
thaumatin-like protein and Xa21. He has built two Transgenic Greenhouse
Facilities at TNAU with funding from the Government. of Tamil Nadu and
DBT.
- His transgenic lines are awaiting clearance from DBT for field
trials. He specialized in transgenic plant technology and molecular
plant pathology and trained at University of California, Davis, John
Innes Center, UK and the Scripps Research Institute, La Jolla, USA. He
is currently engaged in evolving transgenic lines of papaya expressing
resistance against papaya ringspot virus, evolving transgenic banana
expressing enhanced shelf life using elite banana cultivars of Tamil
Nadu.
- He is the editor-in-chief of a plant molecular biology journal
published from Tamil Nadu. He is a member of the Institutional
Biosafety Committees of the following research organizations such as,
Sugarcane Breeding Institute, Coimbatore; Bharathidasan University,
Thiruchirapalli; PSG Institute of Technology; Institute of Forest
Genetics and Tree Breeding; Quinquiennial Review Team on Spices
Research; and Tamil Nadu Biotechnology Board, Coimbatore.
Maharashtra Hybrid Seeds Company (Mahyco), the Indian partner to
American seeds giant Monsanto used a DNA construct containing the
cry1Ac gene, a CaMV 35S promoter and the selectable marker genes nptII
and aad to transform young cotyledons of brinjal plants. A single copy
elite event, named EE-1 was selected and introduced into hybrid brinjal
in Mahyco breeding program.
Mahyco donated this technology to three institutes-Tamil Nadu
Agriculture University (TNAU), Coimbatore; University of Agricultural
Sciences (UAS), Dharwad; and Indian Institute of Vegetable Research
(IIVR), Varanasi; and has made this technology available to small,
resource-poor farmers for free. This was done to ensure the
availability of technology and extend its benefits to the largest
number of farmers. The major difference between the Mahyco's hybrids
and that of the public institutions is that the farmers retain their
rights to save their Bt brinjal OPV seeds for the next season.
Bt brinjal was tested for four years at over 60 locations between
2004-08, with multi-location trials conducted by Mahyco, and
independently by the Indian Council for Agricultural Research (ICAR)
under the All-India Coordinated Research Program – Vegetable Crops
(AICRP-VC). Large scale trials were carried out in 2007 and 2008 under
the supervision of the Indian Institute of Vegetable Research (IIVR).
The results of the agronomic trials have indicated that in Bt brinjal
crops show increased marketable yields by 71 percent over non-Bt
counterparts. A 60-70 percent reduction in pesticide spraying for FSB
control was recorded across the trials. This is reflected in the
Economic Threshold Level (ETL) data for FSB, where ETL was crossed on
an average of 0.94 times in the case of Bt brinjal plots, whereas this
number ranged from 7 to 7.4 for conventional brinjal hybrids and
varieties. Putting these benefits together resulted in a net gain
of Rs 50,000-60,000 per hectare when Bt brinjal plots were
compared to conventional ones.
Bt Brinjal - The journey so far...
2000: Development of Bt brinjal
at Mahyco. Brinjal transformation
initiated at Mahyco.
Gene:
cry1Ac (B.t.k. strain HD73), nptII, CaMV35S promoter, construct from
Monsanto and transformed by Agrobacterium tumefacians-mediated method.
2000-01: Lab and greenhouse
evaluation for efficacy.
2002: Biosafety tests like
pollen flow studies, were taken up along
with back-crossing program into different hybrid parents initiated.
2004: Multi-locational field
trials were conducted in 11 locations with
five hybrids [Mahyco's MHB-4 Bt brinjal, MHB-9 Bt brinjal, MHB-10 Bt
brinjal, MHB-80 Bt brinjal and MHB-99 Bt brinjal]. This was also the
year when Indian Council for Agricultural Research (ICAR) took up
trials with the same hybrids under the All India Coordinated Research
Project on Vegetable Cultivation in 11 locations.
2005: Three more new hybrids
were assessed by the company [MHB-11 Bt
brinjal, MHB-39 Bt brinjal and MHB-112 Bt brinjal] and ICAR in the same
year in 11 centers.
2006-07: After the permission
of the GEAC, the extensive field trials
were carried out in Karnataka, Goa, and Maharashtra at five places. Six
popular varieties - Kudchi, Malapur, Udupi, Gulla, Rabakali, and Goa
112 - cultivated locally were modified genetically and used in the
field trials.
2008: Pollen flow tests and
extensive trials.
2009: Detailed compositional
analysis. On Oct 14, Bt brinjal was
cleared by GEAC for release.
2010: On Feb 10, it was put
under moratorium by the government.
Bt brinjal Event EE-1 contains three
genes at a single integration site namely:
- The cry1Ac gene derived from Bacillus thuringiensis (Bt) which
produces an insecticidal protein. The cry1Ac gene is driven by a viral
promoter, the cauliflower mosaic virus (CaMV) 35S promoter. The Cry
(crystalline) 1Ac protein (also called Bt protein) encoded by the
cry1Ac gene belongs to a diverse family of insecticidal proteins with
specific toxicities to certain groups of insects. This Bt protein
encoded by the cry1Ac gene is highly specific to lepidopteran insects
including fruit and shoot borer (FSB), which is a major pest of
cultivated brinjal.
- The nptII gene which encodes an antibiotic resistance gene (also
referred to as a marker), neomycin phosphotransferase, which allowed
modified brinjal plant cells to grow in the presence of the kanamycin,
and therefore be selected in the genetic engineering process, while
inhibiting the growth of non-modified cells. It has no pesticidal
properties.
- The aad gene which encodes another antibiotic resistance gene
O-aminoglycoside adenyl transferase (aad). The aad gene is also a
selectable marker but it is not expressed in Bt brinjal plants because
it is under the control of a bacterial regulatory sequence that is not
active in plants.
Rahul Koul in Gurgaon